diff options
| author | Keith Busch <kbusch@kernel.org> | 2025-01-23 07:35:43 -0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2025-01-24 10:53:56 -0500 |
| commit | 931656b9e2ff7029aee0b36e17780621948a6ac1 (patch) | |
| tree | 6f2c1558a03bc4ed547b12bd33e614fd014201ba /arch/x86/include | |
| parent | 86eb1aef7279ec68fe9b7a44685efc09aa56a8f0 (diff) | |
kvm: defer huge page recovery vhost task to later
Some libraries want to ensure they are single threaded before forking,
so making the kernel's kvm huge page recovery process a vhost task of
the user process breaks those. The minijail library used by crosvm is
one such affected application.
Defer the task to after the first VM_RUN call, which occurs after the
parent process has forked all its jailed processes. This needs to happen
only once for the kvm instance, so introduce some general-purpose
infrastructure for that, too. It's similar in concept to pthread_once;
except it is actually usable, because the callback takes a parameter.
Cc: Sean Christopherson <seanjc@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Tested-by: Alyssa Ross <hi@alyssa.is>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Message-ID: <20250123153543.2769928-1-kbusch@meta.com>
[Move call_once API to include/linux. - Paolo]
Cc: stable@vger.kernel.org
Fixes: d96c77bd4eeb ("KVM: x86: switch hugepage recovery thread to vhost_task")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/include')
| -rw-r--r-- | arch/x86/include/asm/kvm_host.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 2f442701dc75..f378cd43241c 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -27,6 +27,7 @@ #include <linux/hyperv.h> #include <linux/kfifo.h> #include <linux/sched/vhost_task.h> +#include <linux/call_once.h> #include <asm/apic.h> #include <asm/pvclock-abi.h> @@ -1466,6 +1467,7 @@ struct kvm_arch { struct kvm_x86_pmu_event_filter __rcu *pmu_event_filter; struct vhost_task *nx_huge_page_recovery_thread; u64 nx_huge_page_last; + struct once nx_once; #ifdef CONFIG_X86_64 /* The number of TDP MMU pages across all roots. */ |